488 



till they acquire a dark cinnamon colour, which coincides with their 

 sexual maturity. They breed in barley more readily than in oats, 

 rye or wheat and cannot breed in standing millet, peas, sunflowers or, 

 generally speaking, in grains with a strong shell. Stores with iron 

 roofs are more subject to fluctuations of temperature and provide less 

 suitable conditions for C. granaria. The degree of moisture has a 

 still greater effect, and should it be possible to keep the moisture of 

 the grain below 11 per cent., the pests cannot breed in it. Currents 

 of air have an indirect effect by lowering both the temperature and 

 the degree of moisture and also a direct one, by disturbing the weevils ; 

 light has no effect at all, for although the weevils avoid a bright light, 

 they adapt themselves to it very rapidly. Several experiments are 

 described, which were undertaken in order to ascertain the amount 

 of damage done to grain ; in one experiment, 10 pairs of weevils 

 were put into 600 grammes of grain on 28th May, the moisture being 

 kept at 19 per cent. ; at the beginning of winter, 2,000 beetles were 

 found inside this grain, of which 112 grammes were destroyed. In 

 another experiment, 10 pairs were placed, on the same date, in 350 

 grammes of grain, the moisture of which was 16 per cent. ; at the 

 beginning of winter, 1,000 weevils were present, the amount of grain 

 destroyed being 65 grammes. In a similar experiment, where the 

 degree of moisture was 14 per cent., 440 beetles were found and about 

 33 grammes of grain destroyed. Remedies are only indicated in a 

 general way, but include drying the grain and keeping the moisture 

 in the stores, etc., at a minimum, as well as the use of carbon bisulphide, 

 naphthaline and tar. A high temperature tends to increase the 

 effectiveness of carbon bisulphide. 



Andrews (E. A.) & Tunstall (A. C). Notes on the Spraying of Tea. 

 — Indian Tea Assoc, Calcutta, no. 1, 1915, 75 pp., 9 plates. 



All spray substances, used against tea pests, should be applied as 

 soon as possible after the bushes have been plucked, consistent with 

 applying the insecticide at the proper stage in the life-history of the 

 insect. The Scarabaeid, Serica assamensis, attacks the tissues of old 

 leaves. The bushes and the weeds beneath them, should be sprayed 

 with lead chromate, preferably towards evening. The beetles and 

 larvae may be captured in large numbers, in the daytime, by turning 

 up the surface soil. Nitrolim forked into the soil round the bushes 

 gives good results. The Chrysomelid, Diapromorpha melanopus, eats 

 partly through the succulent stem of the shoot, eventually causing 

 the leaves to drop. This insect comes from the jungle, and the de- 

 struction of the latter is the best means of eradicating it. The larvae 

 of the Bombycid moth, Andraca hipundata, frequently defoliate the 

 bushes. Their habit of spending the day in clusters on the stem 

 renders their capture easy. Stauropus alternus (the lobster caterpillar), 

 can be controlled by spraying with lead arsenate. The eradication 

 of the Zygaenid, Heterusia magnifica, is difficult. Spraying, if adopted, 

 must be carried out with the object of driving the msects into a small 

 area, when they can be easily caught. The larvae do not eat sprayed 

 foliage, but can travel a considerable distance to an unsprayed bush. 

 Spraying with lead chromate should begin some distance from the 

 affected area and should be carried to the centre of this. Migration 



